In a recent eBay purchase I got four pens - one Platinum pocket pens, two look-alikes for it and one Hero something.

One of the Platinums came with a cart in it, which I washed out and refilled. The two look-alikes did not have carts, so I looked and figured I could try a Parker Cartridge - which did not work - it was a used cartridge, but just did not seem to fit.

Is there any other cartridge out there which can somehow be convinced to sit and play pretty in a Platinum brand pen? If not, can anyone tell me a good mail order source for these things? Not every place seems to carry them. And then, of course, when I am paying postage I am tempted to, you know, make it really worth while...

Thanks in advance for any help I get here...