Try Epps. They are the distrubutor for Old Western Scrounger. OWS lists .351SL at $34.95US per 20. Made from .357 Rem Max brass. Epps may even have some. Graf & Sons, Stateside, lists Bertram brass at $25.99US per 20, $123.45US per 100.
Keep the brass. I have data. Mind you, finding .351" jacketed or .352" cast bullets may be difficult.
