Help searching a component (AM8224-4DC)

Hello everyone,
I know this might not be the best place to ask for spare ICs, but the question is somewhat related to the group.
Yesterday I completed my first N8VEM Z80 cpu card, but I have another S-100 z80 board near completion: an Ithaca Audio Z80 CPU rev.2 card.
I have most of the components needed for this vintage board, and what I don't have I replaced with pin-compatible more recent chips, but I'm left with a missing component: the clock generator.
The manual specifies that the 2Mhz version used a plain 8224 coupled with a 18Mhz crystal, and an 8224-4 (actually, an AM8224-4DC) chip with a 36Mhz crystal for the 4Mhz version.
While the plain 8224 is quite easy to get (there is also a 74' clone), the 8224-4 chip required for faster clock is proving to be very elusive: I checked eBay, UTSource and tried a google search for a reseller. I only one in USA with a small stock, but they only sell to companies.

So, do anyone have some pointers on where to look for the chip? Alternatively, if someone has a spare to sell, I'd love to use it to bring my board up. If I'm unable to find one, I'll settle with a 2Mhz board, as building this board is mostly for the fun-factor.

Bye!
Fabio