I have a 1986 Vanagon Westfalia GL 2.1L 2WD Automatic transmission sticks that in 2nd gear in the morning, when the vehicle is cold.  It usually takes 1-2 km before it will shift on it's own into 3rd gear.  I am located in Ottawa, Ontario Canada.

What are the options and what questions/information do I need to move forward (pun intended).
I phoned a few transmission shops/repair shops who said they "do not touch" Vanagon transmissions.  They were uncertain if rebuild kits are available.  Looking at e-bay I see that Pioneer 752078 Auto Trans Master Rebuild Kit is available for my vehicle year.
Ref: https://www.ebay.ca/itm/Pioneer-752078-Auto-Trans-Master-Rebuild-Kit/383089055734
What else would be required for the transmission rebuilder need to have to do this job?
Should/can I continue to drive my vehicle without inflicting further damage?
Comments/questions/solutions welcome.
StuartOttawa, ONCanada