You know, that's an interesting question since I've never seen one of those for sale.
I did once see a Boyes Rifle for sale at $2,000, but I would suspect that there are more Boyes extant that Mausers.
My suggestion would be to contact the guys at InterOrdinance in Monroe NC. They handle a bunch of stuff like this (including some very nice M1908 Maxims they found in Russia).
InterOrdinance: (704) 225-8843
Ken Strayhorn
Hillsborough NC