Hi Devon,
Personally I would stay away from the HT selection with this prep shade. Here is my reasoning; If the veneer will be thinner (less than 1mm) than it will not be able to block that dark prep, and even going that much brighter I don't think it will make up for it. Now if it is a thicker veneer (greater than 1mm) we could have an issue with it going grey in the mouth (from the darkness of the oral cavity) due to it not reflecting back enough light.
I would either go with the Value 3 (same block as new MTBL3) that you are looking at or an LTBL3 (if it is less than 1mm thick). If you are in the states and can get the MTBL2, that may be an even better choice and if it is slightly bright you can adjust the value down very easily.
I hope this helps. Have a great weekend!