Hi there
I'm in the same boat as you (though with 1500 hours). About to be made redundant from medium TP job. I've contacted every B1900 operator I can think of and have gotten no where.....in fact only a few have even responded to my calls/e-mails. Even so, I think buying a rating really is too big a risk. I would only consider it if there were a concrete job offer at the end of it and even then I'd only do it with the redundancy pay off..... wouldn't use my own money.
Chin up, keep at it. Something will come up eventually.
B1900