I see your in MN, where? Buying the bearings from Minnesota Bearing, Tull Bearing or Gopher Bearing will probably be less 50% compared to Clausing. They will be numbered and those 3 places should have them in stock. They won't have a clue if you call and say it's for a Clausing, you will need to take it completely apart ad get the numbers off the bearings. The top bearing looks like it shielded or sealed. That would be good so you won't have to oil them.
If you were in the twin cities I would come and help you, but I'm going on a business trip Wednesday. If you decide to do it yourself Buy a snap ring pliers and if you not familiar with installing bearings, check out you tube. Don't use a punch to hammer on the new bearings. Or you can call me and I can help or I know most of the rebuilders in the area that could help, but they are pricey. send me a Private Message with your number and I can call. Rich
What a legend, thanks for the tips on sourcing the bearings locally and the offer for help, you are too generous. I did get a response from Clausing and the prices are premium to say the least. I will get the numbers from the bearings and reach out to one of these companies. I found a really helpful video from another guy who has done this bearing replacement and a text guide to rebuilding the head that will both come in very useful so I should be well on my way. If I do need more help though I will certainly reach out, I'm in Apple Valley so only a short drive away from you in Cottage Grove.
Clausing 852 spindle bearing replacement and power feed demonstration - YouTube - Video that shows bearing details
http://wentztech.com/WebDisk/Metalworking/Clausing/Freds - Rebuilding the 8520 head.pdf - Head rebuild walkthrough
Prices I received from Clausing (I had them price out basically all the head components for me):
Part# - Description - Price(per) - #Req'd - Note
556-020 - Plate - $379.96 - This plate connects the Spindle shaft to the Pulley set, mine has some play here but not $380 worth, DIY replacement seems viable but I'll save that for later.
044-007 - Bearing (Head pulley) - $64.32- 2 - It's a few bucks extra for a second one as they only have 1 in stock at the moment.
044-016 - Bearing (Head, top) - $41.56 - 1
537-020 - Nut (Spindle) - $7.36 - 1
932-011 - Washer (Spindle) - $1.28 - 1
699-153 - Spacer (Spindle) - $69.08 - 1 - Anecdotal evidence says this is often MIA, I'll have to investigate mine
044-005 - Bearing (Spindle) - $131.03 - 2 - This is the angular contact bearing matched set
708-001 - Oil seal (Spindle) - $25.72 - 1
641-008 - Retainer (Spindle) - $65.88 - 1
8520-16 - Draw Bar Assembly - $117.04 - 1 - I'm going to just make one of these.
547-002 - Oiler - $5.64 - 1
DB4-35 - Oiler - $5.60 - 1
044-004 - Bearing(Overarm) - $29.84 - 1 - Overarm pulley set bearing (top)
044-003 - Bearing (Overarm) - $35.44 - 1 - Overarm Pulley set bearing (Bottom)
Thanks again, I'll update soon.