Marc-Barr, I just enlarged your photo of the refill and I see the end is "belled" for a spring stop. Find a brass refill, cut the shaft with a tubing cutter, have some paper towels handy to sop up the ink that will run out, and "bell" the end with something like a screwhead countersink or reamer. Another idea would be to suck fresh ink out of any good refill with a hypodermic needle and slowly refill your old one (slowly so as to let air escape). I would try the last suggestion first. Might be the easiest.
Tiffany probably produced a certain number of those pens but did not contract with the manufacturer for aftermarket refills because the demand would be extremely low. Rudeness was not called for but the $ weren't there for them to care I guess.
