To have the battery filled you would have to take it to a local motorist and they should be able to fill it for you.
RD 350 LC ContiGO! Tyre Pairs 90/90-18 & 110/90-18 Yamaha RD 350 LC 1981
Foam Air Filter JMP For Yamaha RD 350 LC YPVS 1983 - 1984
Yamaha RD 350 LC 1980-1983 [JMT Lithium Motorcycle Battery]
Yamaha RD 350 LC F2 YPVS 1985-1988 [JMT Lithium Motorcycle Battery]
Motobatt Battery For Yamaha RD 350 LC 1982 (0350 CC)
RAMAIR 43mm Performance Race Foam Pod Air Filter for Yamaha RD 350 LC 1980-1982