bearing/spacer for bandsaw

I'm repairing a shaft on a bandsaw that was run with seized bearings. The original design is a little problematic for me, as the bearings on it are sealed on one side, shielded on the other. This wouldn't be so bad, except that it is used in a woodworking environment, lots of fine dust. And the housing that this shaft and bearings sits in has a giant opening in the middle. I'd like to replace with fully sealed bearings, but one of the bearings is an odd size, NTN 87502. This is basically a 6202 bearing with 15mm bore, 30MM OD, but the inner race protrudes from the sealed side a small amount ~ 1.79 mm There is a nut that secures the inner race to the shaft. I'm wondering if I can get away with a standard bearing here? can I just put a washer in there between the nut and the inner race to give appropriate clearance between the nut and the seal? Why do they not sell these bearings with double seals?

I'm also wondering what kind of inner clearance I want on these bearings. CN or C3? The whole assembly has the main bearing pressed into the housing after the bearing has been placed on the shaft, and snugged up with a nut securing it to a shoulder on the shaft. There is a locking ring to screw in and hold that bearing in place at the bottom of the housing bore. Then the rear bearing is pressed snug into its bore in the housing, and stops against a shoulder on the shaft, and is held snug with a nut to keep it in position. So there is no pre-loading of this system in any meaningful way. this is a bit of a miserable machine to pull apart and put back together, and I'd like to never service it again, so want to put the best possible bearings in.

thanks in advance for any input here,
jon

for the washer needed to replicate original extended inner race, is there anywhere that makes properly dimensioned washers to extend the bearing inner race at all? I can easily enough make one if I must, but I'd much rather get an off the shelf part if possible.

I cut milk bottle plastic washers stacked to touch the sides of a bearing and being a little larger diameter if possible to become a dust shield..yes stacked if needed so they pressure to the bearing side a little.

I'm not sure that plastic washers are going to do the trick here.

This is one of the bearings in question. I'm still not sure why a person would put in a bearing with a single seal and a shield on the other side, when they could use a double sealed bearing and keep the grease in and dust out. Also I'm not sure of the point in the extended/offset flange on the inner race, since the rear of the bearing is at most 10-20 thousandths recessed. Can this be replaced by a normal double sealed bearing instead, since the odd flange seems only available in this also strange to me single sealed/single shield option? the nut seems designed to keep it off of the seal regardless of how far the inner bearing race is proud of the outer one looking from the side.