When I replaced the slave cylinder on my truck it was with the OE part from Burt. IIRC it was price competitive with aftermarket (I want to say about $45). Sometimes you get genuine Aisin parts from NAPA and IPW, though, so it's probably worth checking.
Getting at it is a PITA, but it's not the worst job ever. I wouldn't rule out a hard line, they can rust, too. I have one of those power bleeders that might be handy pressurizing the system to look for a leak. Not sure how I'd get it to you any time soon, tho.
'91 Pickup - Imelda
'08 Tacoma TRD - Donna
'09 Kawasaki KLR650
'12 Gunnar Rockhound 29
"Our task must be to free ourselves from this prison by widening our circle of compassion to embrace all living creatures and the whole of nature in its beauty. Nobody is able to achieve this completely, but the striving for such achievement is in itself a part of the liberation and a foundation for inner security. " --Albert Einstein