Give Liz or Mark at Audiopile a call...they can probably make something up for you if their stock gear is not suffecient for your needs... EWI is good quality gear at good prices and both Mark and Liz are GREAT folks and friends to do business with..
Call one of the big guys (full compass, b&h, markertek, etc) you could probably get one for just a bit over $100. It will most likely will be a ProCo or a Whirlwind. If ProCo it will likely be a StageMaster series snake. You probably won't find an exact snake to your specification. The snake industry is a fairly custom industry. They don't really bother to make odd ball specifications unless they're requested too. That's why you'll find so many 24x4, 24x8, 16x4, etc in basic lengths of 50', 100', 150'. Most likely no retailer will have the kind of snake you'd like in stock. So instead they'll just order you one, which is normal. Every snake I have ever ordered has been custom and usually takes longer to aquire than most other audio gear.
The reason that it is not long enough is because it is a sub-snake, which is designed to link up with your main snake for use on drums. this way you don't need to run multiple mic leads from the riser to the stahe box. You use the sub-snake instead.
Now I don't know what snakes are worth in the US but you may be better off buying either a second hand (make sure you test it and get a warranty) or a standard format one (12x4 or similar).
Try the above links but you might find that it may prove more expensive to get one custom built when compared with one that would have more that you need but be a "standard" item.
The upside of this is if you do upgrade your system to include more channels, you have a snake that will be able to do this.
I don't think you'll find one that small without custom (assuming you want it exactly that way). That Hosa sub-snake is pretty decent. Try ebay for a 50' but you likely won't find exactly that configuration. Most of them are going to have a minimum of 8 inputs and 2 returns, or 12+ inputs and 4+ returns.