Direct answer
301/SR43SW and 386/SR43W share 11.6 × 4.2 mm dimensions. They are not collapsed into one alias because the source maintains separate SW and W drain designations.
Both are 11.6 mm in diameter; heights are 4.2 mm and 4.2 mm. Both are 11.6 × 4.2 mm silver oxide / zinc cells at 1.55 V nominal, but their drain designations differ (SW: low-drain profile versus W: higher-drain profile). Preserve the device-specified class.
Do not infer acceptability from fit alone. The device maker’s complete code and current instructions remain authoritative.