PSRU Gen 3 v 4 Front Seal Information
The manufacturer is Harwal, and you will need to call them to find a distributor in your area. Harwal (East): 802-223-0197, Harwal (West): 303-373-1446.
Harwal has an online 2009 Catalog, and the part number is:
Shaft Bore Width Type Material
90 x110 x 10 ADL FPM
90 mm ID (Shaft size); 110 mm OD (Bore); 10 mm width; ADL=Rubber-coated case, double lip seal surface; FPM=Viton
As of 4/5/2014, the direct link to this product is
8/30/2010: I contacted Kaman Industrial at 916.372.7812 (a Harwal Distributor in Sacramento, CA) and talked to Franko to order the part.
Price: $58.00 US. Add Tax and shipping. (Note: the non-viton seals were $19.00 US).
4/10/2014: I have an update on the 10mm seal SKF part number. Basically the SKF part number is best found by "CR 563449", which replaces the one originally one provided us (CR 563450).
I spoke with SKF which has the prefix on their seals of CR, and confirmed that the 563449 seal was in fact viton and had the correct dimensions. They told me that the 563450 part# was now obsolete and is now the 563449.