Hoyt , and other ILF-type limbs can fit the Gamemaster. However, the ILF fitting must be removed and a bushing put in it's place. It is a simple and cheap procedure, and a couple places sale bushing kits for those that may not want to provide the materials themselves.
ILF limbs are generally offered in 3 lengths-long, medium and short. The Hoyt target risers, and most other target risers generally come in 2 lenghts--23" and 25". Hoyt's Helix comes in a 25" length, the Nexxus in both 23" and 25".
For a Gamemaster with short ILF limbs, you will have a bow of 62", for mediums-64", and Longs-66". Remember if you buy the ILF limb that most are weighed on a 23" or 25" riser---the GM riser, being shorter, will add some pounds.