I found a wonderful little free online service provided by http://www.partsvoice.com to for dealer OEM parts inventory.

For example, I plugged in the part number for the STi short block, 10103AB440, and this gives the results of Subaru dealers that show it in inventory, along with the date their inventory on that part was last confirmed. There are no prices, but there are phone numbers for each dealer.

I thought some other might find this service usefull.

* I thought it was funny that out of the 13 STi shortblocks in the country Mastro Subaru has 4 of them.