I responded to a craigslist ad selling a vintage barber's chair, also mentioned an antique Russian made leather strop. I offered him $10 for it, he said he figured it was worth more than that. I told him I didn't know what it was worth but I couldn't afford to speculate about its value as an antique but I might pay in the 20's.

What is a fair price, considering that I don't know when/where it was made or whether it is in good condition?

I'm a newbie here, and I don't even currently own a straight razor (probably will be purchasing one in the near future). like the idea of having a nice vintage piece, but I don't want to overpay.