Just made up some wrapped arrows so at this time I can't say if it is possible to replace just one but I kind of doubt it. For my wraps I bought some vinyl at a sign makers shop. Used fetching tape with a dab of Bonnings glue front and back and they seem to work fine. Solid color but they still look sharp and cost about $3.25 per dozen.
As to the width of the wrap I think just tell Onestringer what shaft you are using and he will give you the correct wrap. For 11/64 wood shafts I cut my wraps 1-1/8.
The guy at the shop wraps his arrows with the same stuff and told me to keep the over lap to no more than a 1/16 or 1/8 or the balance will suffer. What I did was to measure the shaft diameter with a caliper, multiplied by 3.146. That gave me a very mall overlap.