Where can I find a unmarked belt for my antediluvian wash mechanism? I have a Whirlpool Imperial Seventy wash machine. The model...

I have a Whirlpool Imperial Seventy wash machine. The model number is LA78OM and the serial number is L-7800XMNO. My bf call a parts store, and they said without the previous belt they couldn't assistance us. We thought we had replaced the belt, but the spanking new belt wasn't the correct belt, and we threw the old belt away by this time. (Yes stupid us). There have to be a way to find a belt to work near my washer. Besides the belt breaking, everything else about the washer is lately fine. I have be paying to wash my clothes, and bring them home to dry, but near gas prices going up, I can't afford this anymore. Please direct me in the right direction.
Stinky towels?
Answers:    move about to any repair shop with that information-they will know -you dont call for old belt-good luck
Wet dog smell...?
Go to the Whlrlpool net site, armed with the model and serial number. If you can't find the info directly next to some surfing, send a record to Whirlpool's Contact Un link, and they should be capable of help.
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