Bearing and Transmission in Regina has a good selection of belts if you cant find the right MTD ones. Take the old belts in and they can probab;y match them up.
Thanks! That is were I got the belts for my Rototiller, great Place.
My Dad actually bought the belts from Canadian Tire, $28 for the set, not bad price.
My concern was the letter B instead of A, but I have installed, and they seem to work fine, time will tell.