http://www.delta-transparts.com/ They also have some transfercase parts and might have the 300 parts and seals your looking for. You will have to set up an account and provide credit card info for billing. That place is actully set up to supply transmission shops but I have not had a problem buying parts as an individual. Just don't get the wholesale price. If you have a buisness license you might be able to get the discount.
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