Ben E King's Stand By Me is one of those beautiful classical songs where the Bass pretty much makes the song itself, which is why It pains me that I've never managed to get the sound quit right, So what I'm wondering is, Can I even get it to sound right on an Electric bass or would I need to get myself an upright to get it sounding like it's supossed to sound? And If It can be done on an electric bass I'd like to know how. I've got a Jazz bass and a P bass if that helps...
Duplicating the sound of a double bass with an electric is tricky. I'd start putting flats on one of you current basses, sticking a foam mute under the string close to the bridge, and plucking the string close to the neck (or even over the fretboard). For this particular track, you may add a touch of reverb. From there, it's all about experimenting: try both your basses, all possible pickup configurations, move the foam mute around to change the dampening, adjust your plucking position... You should have the tools to get a usable sound. No need to buy an upright. Unless that's what you want, of course. Then go for it!!