You'll find more on this subject in the archives - both here and on the NCOWS Forum.
Here's a short compilation that should help.
A pair of button-fly Levi 501's - after the trouser loops and left rear pocket have been removed and suspender buttons installed are period-correct for the era.
'Wranglers' aren't, since they came about after the turn of the century.
As to other materials - you'd most certainly have cotton.
'Nankee' trousers - a yellow-brown type of cotton cloth - would be common and about the time of the California Gold Rush - Levi Strauss was making stout trousers from tent cloth.
They'd eventually become known as 'Levi's pants' by the miners - later to be known as 'Levi's'.
He adopted the Indigo Blue as a hallmark to identify his product.
The copper rivets, Orange thread, oilcloth identifying ticket and leather label were in use and patented or copyrighted up until about 1908.
Anyone cowboying would've sought out the toughest pants he could find for the work ahead - and Levi's filled the bill - as did the various tailor-made stuff.
Wool and wool-blends were as common as cotton - plain and in varying patterns - both dark and light - and I've seen the wildest plaids you can imagine in period photographs and daguerreotypes.
Must not've been many available mirrors...
Remember - over time - aging and fading happens in photographs - and that doesn't properly show 'true' colors.
WAH does a fine representation of available trousers - as does COWS and I'm sure - others.
One other thing - at the time - pretty much all clothing was made-to-measure - and though the 'style' was similar - fit varied.
There was no crease in the trouser leg - a crease indicating that you bought your goods over the counter and the 'proof' was the folded crease line.
Though 'belts' have been around - 'trouser' belts haven't, since there were no trouser loops.
They're essentially a turn of the century invention.
Braces, galluses, or suspenders - all were used during the time - as were the high-waisted trousers.
Suspenders were more than common - but not all men wore them.
The small 'Ivy League' adjustment belt at the back of the high-waisted trousers was often snugged-up tight - and preferred by those who didn't like suspenders.
And 'showing' a pair of suspenders was akin to going in public with your undershirt on and without a shirt - it wasn't approved of and indicated a lack of manners.
Remember - we're talking the Victorian Era, here - and folks were 'far' more 'proper' than today.
They were effectively 'hidden' - both from view and from entanglement - by vests and coats - and 'all' men wore those as working dress.
If you didn't like wearing a pair - for reasons best known to yourself - then the adjustment belt was available at the rear and could be tightened as needed.
Many men did this - using friction to hold their pants in place.
Some would wear a sash - but that was generally a Southwestern affectation - drawing from the more colorful styles of the Mexican Vaqueros.
The sewn trouser loop wouldn't become a 'staple' of men's furnishings for many years - despite what's seen in the 'John Ford Reference Library'...
I 'do' like this quote from the Dodge City Live Stock Journal:
"A fashion item says that leather belts are in favor.
They were in favor here at one time.
Perhaps there was a difference in them.
Ours were studded with cartridges, and were very popular..."
Another good source of information is the Time-Life series titled 'The Old West' - available at your Public Library - and the reprint catalogs of both 'Sears, Roebuck & Co.', and 'Montgomery Ward & Co.', that pre-date 1900 are invaluable for showing exactly what was available during the time frame.
Any questions - send me a PM.
Vaya,
Scouts Out!