One thing I'd suggest in regards to older cameras like a Pentax K-2, if
one is particularly fond of such a model, is checking on-line auctions
for a good functional example to purchase.  Then one can use the
problematic original for parts and of course any lenses and accessories
that one already has will be a predictable fit.  I just checked eBay and
found two functional, apparently very good condition K-2s going at
$177.50 and $225.00, respectively.  A third had a $250 'buy-me-now'
announcement with a reserve auction price which would be somewhat under
that (maybe $200?). Obviously the K-2s are still quite desirable by
these prices, but a proper repair and cleaning of the original could
easily reach these levels.  As with all online auctions, check the
reputability of the vendor/seller by the comments they have garnished
from past transactions.  I've had very good luck in this way in regard
to buying accessories (lenses, OEM straps, bags, shoe adapters, etc.)
for my slightly older screwmount Pentaxs and similarly-lensed cameras.
I even bought a Soviet-era Russian Zenit on eBay mostly for its
screwmount zoom lens, though the camera is an incredibly interesting,
albeit clunky, piece.

A warning though: online auctions can be very additive!  I first caught
the 'fever' with old tobacco pipes and then after a brief remission
caught it again regarding Kodak slide projectors and accessories and
finally the SLR camera stuff.  In over fifty purchases though I don't
have any complaints.  A few things were a little disappointing but in
those cases the purchase prices had been very negligible.

Larry Buhr
University of Nevada, Reno