ATM 6"-8" and 10" - 12.5" mirror/other components

[Mike Pence <mpence@avalon.net>]

Hello.  

I'm building two scopes, one for myself and one for my parents. I'm
hoping someone either has a used mirror or knows where to go to get
great prices for mirrors.  I want to find somewhere around a 6" or 8"
with an f/ratio of around f/6.  And for myself a 10" or 12.5" with an
f/ratio of f/6 or longer.  

I just found a 10" mirror of an f/ratio of between f/5.6 to f/7.  He is
selling it for $100, but it is not coated.  It is, however, ground and
polished.  My concern is whether it is ground correctly and if that were
the case, I'd have to have that redone since I don't have the time nor
experience to do it.  

Any thoughts/advice?

Thanks.
Mike