Spark plug question

My bike (1981 KZ750 LTD) has got a damage spark plug cap. I recently changed all spark plugs (using the recommended specs. NGK B8ES) - and the current spark plug cap on the bike are LB05F - I imagine that replacing them with the same model is fine? Also is it a good idea to replace the wiring leading to the coil in the process? If so, where is a good place to find these cables?

I am sure these are rather daft questions, but I am a little lost and obviously not very mechanically inclined