The Kinesis Freestyle Edge has 12 such keys in that position. The mechanical gaming version (RGB) allows them all to be arbitrarily mapped, and function keys are one good use of them.
Thanks - both your suggestion and @davewongillies are close ... but my ideal keyboard is still the "87 key" layout with the inverted T, but with 12 function keys on the left. On modern PCs it's hard to live without the F11 and F12 keys.
I'd even settle for a 12 key keypad on the left as well - that might be more doable. Looks like I might have to build this myself from scratch ...
There are a few commercial keyboards out there that offer this. I was going to suggest the Logitech G110 that I use, but it appears that model's no longer manufactured. Still, there are others.