rivet question

[2nd District]

I have a question on the rivets used on the vent windows during the process of replacing the rubber. the rivets the resto companies (brothers, lmc etc) are what ive been using and my question is does anybody have a source or a part number or a place where these rivets can be purchased in more of a bulk manner? like 50 at a time for instance, and not the small amounts offered by these companies? the rivets seem to be 5/32"body diameter, 9/32" length, and 1/4" diameter head. Ive searched some rivet companies on line but cant seem to find this combo anywhere, any help would be great thanks