I looked at your brochure and it says you have a Super Lube axle / bearings not the sealed bearings.
I looked a LCI and a sealed bearing hub is 500 dollars, that's crazy.
Can you see a Part number on the axle and then check on line to find out what type you have.
Check out this web site and compare it to your hubs.
SuperLube Trailer Wheel Hub/Spindles Owners Manual
Someone else will chime in pretty soon.