I go along with those who suggested PVC pipe extenders. They work great on 'church hall tables'. At home, I have an old wooden table (dropleaves) that DH fitted with PVC legs, which he then PAINTED; probably a spray can of enamel. The legs just blend right in with the wood. Just be sure to measure the diameter of the legs if using a wooden table. You want a snug fit so it is not wobbely.
I am sure that buying a 4'-6'length of PVC and 4 end caps is only a few $.He made an extra set, which we gave to a friend for a donation of $5 to the quilting fund :-)