The Deck Model numbering system is a bit confusing. The best as I understand it, the first two digits (38) indicate it cutting width.
Haven't figured out what the third digit indicates.
The 'U" means it was made in the USA.
All decks seem to start with "1111" being the first production. 1112 would be the second generation, and 1113 would be the third, and etc.
Yours seems to be the 6th generation of the 38" deck.
In the CPE-2 Parts Manual, sometimes you see a distinction in part numbers based on the "1111" number.
The belts you are looking for are:
*
IH-490489-R2 PTO Belt (3/8" x 80")
*
954-3002 Spindle Belt (1/2" x 72")
That is the best I can give you.