Here you go. These links are for the Lortone LS-12 slab saw which I just updated. My other saws already have the better pulleys. (Covington 16in and Lortone LS-10, 10in)
LS-12 arbor pulley
https://www.amazon.com/gp/product/B007YLTRXYLS-12 Motor pulley
https://www.amazon.com/gp/product/B003N17JKCNote: These are also usually available on eBay so shop around for best deal.
eBay can be faster since after payment the better sellers have to ship within 24 hours after payment. Amazon is slower especially when you choose free shipping as an option.
For eBay buy from sellers with at least 50 ratings and at least 99% positive feedback.
In the above example the only place I could locate the 2.25in pulley was on Amazon.
Note also the part numbers since there are more than one groove size. Usually for lapidary you want the 4L size which also equates to "A" belts. I went with Amazon for the 3.95in size since the part number matched better than the eBay auction and price with shipping was the same.
It also might be possible to buy these pulleys on bigger internet websites like Grainger and MSC but I like using Amazon or eBay due to their return policies.
For belts the sizes are:
LS-10 is 4L-320 belt
LS-12 is 4L-360 belt
Covington 16in is 4L-420 belt (This is the budget Covington 16in which I bought many years ago so check your part numbers and .pdf files to match any current models.)
I bought the lower priced belts on Amazon but would be curious as to what others are using since there are more expensive rubber woven belts that are more durable. The issue is the cost to replace belts if they get burnt up when a blade gets stuck.
https://www.amazon.com/gp/product/B00E42BRF2https://www.amazon.com/gp/product/B00NUQQR9Ehttps://www.amazon.com/gp/product/B00E42C4W2