I did one pretty close to that with the snowboard tuning instead of pricey ski vises - a Harbor Freight Workmate style bench ($10 or something like that on close-out last summer) and a set of the T style snowboard tuning clamped to it for $15 off season deal. Need wood or even a section of plywood extensions for the longer skis and maybe a binding lasso to complete the set-up.
If you have a Harbor Freight they have a replacement adjustable height portable Workbench that is more money but still cheaper than the Swix style portable tuning tables. It makes for not being as portable (still could fit in an SUV or minivan but luggable.)
Otherwise- look at the thread (you did a search before posting I'm sure) Philpug has with the portable folding saw horse and a sheet of shelving- priced out at one of the home improvement stores for less than $50. Heavier than the Swix tables but could be pretty close in space depending on the shelving length used.http://forums.epicski.com/showthread.php?t=65563