I have a Ultra by Murray - 8HP - Model G2784030 - looking for replacement belts. Can you help me locate somewhere I can purchase and what size belts they are

Hi,
Well, I broke it loose to provide this without it being attached to an old post. The company has changed hands which makes things a bit muddled. An HTML set of drawings is at:
Murray st Parts Diagram Index for G2784-030 (http://partsandservice.com/html/Murray/st/stg2784-030.html)
And the drive belt is #579932MA, and auger belt is #585416MA. Sources seem to say that the first is a 3L 33.13 belt and the latter is 4L 38.1(some conflicting info there.)
The first 579932MA appears to be a Stens #238-033, Oregon #15-014 or RCPW #265-525.
The second 585416MA appears to be a Stens #248-038, Oregon #75-438 or RCPW #265-524.
RCPW stands for Replacement Commercial Parts Warehouse at (800)937-7279 which I have little familiarity with.
Putting in the numbers at Sears PartsDirect shows them available there at:
http://www.searspartsdirect.com/partsdirect/index.action
Putting in the numbers at Outdoor Distributors (888)656-7278 gives the following number changes: 579932MA changes to MUR-173324SM and 585416MA changes to MUR-585416MA and has an extremely old number of 37x 137. Their parts lookup page is at:
Murray Lawn mower Parts, Murray riding mower and lawn tractor parts (http://www.outdoordistributors.com/Murray/Murray_Main.html)
The second two I know well.
Also, they are listed at eReplacement Parts which I occasionally use for parts for power equipment parts(not lawn & garden variety.) at:
Lawn Equipment Parts - DIY Lawn Equipment Repair : eReplacementParts.com (http://www.ereplacementparts.com/lawn-equipment-parts.html?gclid=CJyk8-Tp87ACFQoHnQod9xqd8g)
Additionally, they are listed At Order Tree(the nation's largest OPE distributor) with part numbers BSM 579932MA and BSM 585416MA at:
OrderTree.com (http://www.ordertree.com/)
Look at the prices and the availability which may preclude price as the only consideration. There are many dealers who carry the Stens and Oregon parts.
Peace,
Clarke