350 ohm isn't a standard size, so just use one that's close.
:What can I use for the replacement for 350 ohm 1/2 W. Flex resister? I have one which is burned out in a Crosley Model 517. The Rider's schematic is found on page 8-13. It is resister number 23 in the schematic. Thanking you in advance for any assistance.