New sheets
If It were me,Id measure my old ones,length and diameter and use same. For the jib sheet, use one continous line (winch to clew to winch) and fasten center at clew. push center of line thru clew hole,then bring rest of line thru it and tighten,pass port and stbd thru blocks and put figure eight knots in end. For mainsheet,attach line to mainsheet block with a bowline (visit library for info) reeve thru boom block same as original and end at mainsheet jam cleat. Tie figure eight in end of line. I have found this to be simplest way, and can be easily done by owner. Good luck red