Back in the 70s SA hubs had an oil port and relied on infusions of oil to keep things lubed. They did ooze oil a bit but worked very well. I took my RF3 hub to the LBS and they worked on it using YouTube instructions as IGH hubs are very rare here. After a while they figured that two different types of grease were needed. Having read about the oil lube I applied a few ccs of 5/20 synthetic oil through the shifter port on the drive side of the axle and it worked well even when ridden in below zero F temps. When it gets noisy a little more oil solves that. Ordinary Jagwire cable housing and regular cables work fine and the housing can be bought by the foot. If you don't have a cable/ cable housing cutter and you take in your cables and housing to the LBS they can cut them to fit there. Be sure to lable the housing and take a picture or two before you didisassemble the cables so you can put them back as they were. Buy a chain breaker and cut new chain to length yourself and buy some extra sprockets for the hub to replace with the chain if it skips after putting a new one one. I could buy the housing at $1 per foot, the cables for $5 each, a sprocket for $7, a 7/8 speed KMC Z chain for $10 and a nice Park chain breaker for $17. You got hosed by the shop. With a little practice you can replace chain, sprockets, cables and housing in an hour or so.