I'll second the good report on the 1902 tunic. I changed out the buttons to gutta-percha plain buttons and dyed it a field brown for my Boer Scandinavian Korps impression.
Also from What Price Glory I can report excellent quality of their 1892 Cavalry bandolier, five front pouches and four rear mounted. Pockets actually fit paired 6.5mm Mauser clips and closed with a little wet molding and Lexall conditioning.
Likewise their 1902 Garrison belt, revolver belt pouch and flapped holster were great.
Tommy's Pack Fillers has nice selection of food tins, boxes, First Aid and similar accessories for your impression, 1899 - WWII.http://www.tommyspackfillers.com
Liberty Tree Collectors gets in some obscure stuff to help round out an impression. Sometimes a bit careworn from storage, and pricey at times. but when you're looking for Swiss belt cartridge pouches for 6.5mm clips, . . . They're getting stuff in all the time, so if you see something new jump on it quickly to get the best selection as far as condition.https://www.libertytreecollectors.com/productcart/pc/ltc-default.asp
Finally, S & S Firearms is a good source for items, but I have to report that I've not been pleased with some of their leather reproductions. Storage must be a problem, either that or it's stuff coming from Pakistan or India. It has been dry rotted more often than not and straps and areas around snap downs have cracked. Hardware and the like I've had no problems.http://www.ssfirearms.com/default.asp