They are a good caliper, just when compared with aftermarket ones they are very heavy due to being cast iron, as opposed to alloy of most aftermarket.
You can recondition, but get no warranty but is simple enough depending on how far gone/bad they are, around £30 per side to do, assuming the pistons will come out.
When I did mine just after I bought the car on one side 3 out of 4 pistons were seized, unseized one came out no bother, but other three were a serious pain, with two pistons(both in same half) needing me to make a tool that expands when you turn it to grip the inside of the piston, and I had to use a 4 foot lever onto this as well, even though heated etc.
Anyway did all the seals worked perfect for a year, then started getting sticky again, got some recon ones with stainless steel pistons, 3 years on perfect.
I got my seal kit from biggred.co.uk ace man/company to deal with.
tabetha