Yes, they were the ribs I had from Jack Stack's BBQ. However, they charge a premium ($60-80 for 2 racks) and I was hoping to make them a little cheaper. I'm not sure what riblets look like. The ones I'm looking for are about the size of a baby back rib.
Check the ethnic markets like Jons on Vermont, Super King on San Fernando Rd near the 2 fwy or some of the other ethnic markets. Lamb is usually cheaper at these places. Good luck and use plenty of garlic and rosemary!
Lamb back ribs are a problem. Baby back ribs were born from the desire to have boneless pork loin roasts, with the rib racks being a byproduct. Beef rib racks are a byproduct of boneless beef rib roasts. But there's not much demand for boneless lamb rib chops or roasts.