Renting a Hosford wall thickness gauge.

[Quack me up!]

Looking for opinions here. Seeing as I can't find someone with one of these gauges closer than about three hours away from me, I have an idea and want your input.
I was thinking of buying one of these gauges and then offer it for rent to fellow PGCA members. I can't justify buying it just for myself as I'm not fortunate enough to buy and sell very many double guns.
I would just keep the gauge here at home and when someone wanted it I would send it out to them however they want, USPS etc. They would just pay the rental fee and send it back to me. I'm not sure how much would be a fair rental price so I'm looking for input on that also. Maybe $50.00 for a week or ????
Let me know what you guys think. Maybe there's enough of these already floating around between members where this wouldn't be feasible. I'm not looking to get rich of off it by any means just maybe offset the initial purchase price some what.
Thanks for any opinions, pro or con.
Bob