go here
https://shop.mecoa.com/shopsearch.asp
put that part number 85-5802 in
and it will show you this page
Item Number Description Stock Status Price
85-5802 LOW SPEED IDLE DISK W/2 O-RINGS GOOD $13.75
the stock status is good
the price is 13.75 with the o-rings plus postage
enter the quantity you want
check the order box
click "continue"
enter your information
check the box that says you accept our terms
click continue
review your order
click continue
enter your payment information
click continue
you will receive a confirmation email