What about a Tonebender clone instead? Or a Swollen Pickle clone? They're somewhat similar to Big Muffs.
You could also check out the MXR El Grande... it's more controlled than the Big Muff is, built for bass, and very compact.
Or you could reconsider your size requirement and wait for the Bass Big Muff.
You could also check out the MXR El Grande... it's more controlled than the Big Muff is, built for bass, and very compact.
Or you could reconsider your size requirement and wait for the Bass Big Muff.