Since this is one of my hobbies, I've already made a LINGO box game for myself and friends. It's not really that tough. I'm always buying old games at second-hand stores and recycling the parts for new projects. Admittedly you have to adapt for limitations, but it works. A 25-square grid covered with clear laminating plastic allows for the use of a dry-erase pen. Two permanent player LINGO cards (one red, one blue - using just one pattern of filled positions already used on one tv episode) - and I'm not going much farther, as if Endless Games ever decides they want to go this route, I'd like to have them look this over as a model. For what it's worth, though, because the host must hand-write the letters on the game board, the bonus round runs 3 minutes (using a classic sand timer) instead of 2. It's not all that expensive to make. I recently talked with Kevin McNulty at Endless - one problem he has to deal with is that retailers - especially the big gorillas like Toys R Us and Wal-Mart - demand they keep costs down as low as possible to keep prices down, therefore, quality is sacrificed. It all depends on how cheap they can put a package together. Milton Bradley turned down WHEW as a home game, claiming expense. I sent Jay Wolpert a copy that would only have been slightly more expensive than Jeopardy to make - as many were MB Jeopardy parts. Maybe licensing rights were high? Anyway, LINGO is very do-able.
By the way - Endless at one time re-distribuited a classic late 50s-early 60s paper and pencil word game called JOTTO, which involved determining a five-letter word using pretty much the same process as LINGO.