orangeville isn't the ass end of nowhere, since canada post still delivers.
take your pick.
http://www.chainreactioncycles.com/M...?ModelID=38215
http://www.chainreactioncycles.com/M...?ModelID=40551
or ebay.ca and amazon.
com
you wouldn't be able to modify an existing MTB rear hub with the 6-bolt rotor, because if you do that, you wouldn't be able to lace up the hub again, assuming you disassemble the wheel so that it's easier to work with.
the 6-bolt holes for rotors has a larger diameter than the spoke hole circle and this just makes it impossible to lace up or even replace broken spokes on the wheel. Now, if you could tig weld a center lock on the hub, that wouldn't be a problem, but no such things exist, because all hubs are either machined from a single block of aluminum or forged and heat treated.
Now, if you want to try and weld on bolts with some TIG or MIG welding, then the hub would need to be disassembled, all the grease, bearings and spokes would have to be removed, because you don't want to unevenly distribute the heat flow from the steel spokes and bearings. Once you weld the mount on, you'd have to heat treat the hub, because you've most likely changed the properties of the hub from the heat of the welding. The hub can still be ridden without the heat treatment, but it's very likely to crack. Add to this, the fact that you can't even lace up the non-drive side properly, because the rotor mount is in the way.
And if you're still not convinced that it's a bad idea and unworkable, then knock yourself out in trying to modify it, because I'm always interested in seeing people work around problems that can be solved with money, by throwing time at it.
as the saying goes; time is money. even if you work at the minimum wage for ontario, 8hrs would cover the cost of getting a new hub.