That lathe makes me seriously ascared.
Actually, my first thought was, the other things that I could have done with that nice piece of lumber that you started out with.
If you are referring to people modifying or making something similar to the Cowboy Lathes, yeah, thats possible to do that and have something acceptable to do work on your own cues.
When you say the word Mobile, please say that Mobile doesn't mean taking it to a hall for a tournament.
Keep your eyes peeled for good deals in the Machinery Forum.
Quite often you will find a length of used lathe bed, a headstock, carriage, etc.
Motors from Penn State also.
Lots of guys have made their own taper bar set up.
Be patient and buy one piece at a time. There is a wealth of info here and I am sure that once you have all the pieces, many will be more than willing to answer questions.
Keep in mind tho, sometimes unless you know what you are doing, building a lathe isn't a ton cheaper than just out right buying a pre built.
If it is the experience of making your own lathe that you are after, then buy the necessary spare parts that others are selling instead of Jury Rigging things that were never meant to be part of a Lathe anyway.
I once bought a used lathe, (still consider it to have been a great deal Bud), some Hightower parts etc. Todd helped me out with a few extras. I bought aluminum to make a taper bar set up. Not even close to having it finished yet.
I would bet 100% that when I am done, its going to be a super lathe but it won't come in much less than a Mid American or Hightower.
I already have a lathe so this is just for the experience of piecing one together. Cost was secondary to my eventual goal.