Martin,
Let me help you with identifying the bearing you have in your photo. I suggest it is not the LN Single Row Pro. There are not enough balls and there is only a single row ball race.
http://lnengineering.com/resources/2014/03/07/single-row-pro-ims-retrofit/
So to clarify, whose bearing is this -perhaps just another hybrid single row 6204-1RS? Like this:
http://www.ebay.com/itm/1-PCS-6204-2RS-20x47x14-mm-Hybrid-Ceramic-Si3N4-Rubber-Sealed-Bearing-Bearings-/291422240233?pt=LH_DefaultDomain_0&hash=item43da1e7de9
or this:
http://www.ebay.com/itm/6204-2RS-Hybrid-Ceramic-Si3N4-Bearing-20x47x14-Nylon-Premium-ABEC-5-/360461702926?pt=LH_DefaultDomain_0&hash=item53ed31170e
Unless we confirm exactly what product we are discussing ,this will be a pointless mess.
BTW congratulations on developing your plain bearing solution to the IMSB issue. Seriously- this is USA ,we like competition !