I always suggest just asking around, neighbours, granddads, dad, uncles, the "older generation". I aquired 3 very nice atraight razors and a "new" strop for free from my long term barber. Sent them a honemiester will have them back next week. The great thing about this approach is if you aquire it from someone you know, they can mentor you or at least get some tips. Also I like to hear about any history of the blade, interesting stories, how old it is etc..

The most important thing is to make sure your razor is "shave ready" this does not mean "factory shave ready".

EDIT: ANd welcome to the forums