Why couldn't you take a small bar fridge (probably about $150 new), carefully remove a few screws to allow you a view down one side between the outer skin and the inner liner, find a clear spot and drill 2- 7/8" holes from outside to inside.
You could then feed the two ends of a 25 foot coil of 1/2" I.D poly tubing out the side and silicone them in place with about a 5 inch nipple of tubing sticking out of the bar fridge. the coil is inside, of course. Now attach to a recirculating pump with low gph (bleed off flow if necessary).
With a thermostat controler you could have the pump turn on whenever you need the temp to decrease just like a non-inline chiller.
Here's the best part. You are bound to have 'Left over' room to house a few wobblypops to help cool
you down while you iron out any details with your new Barfly Chiller!
Cheers
