I think you are looking for what is known as a melody or tango banjo. four strings, mandolin scale length, tuned as a mandolin (although I suppose it could be tuned CGDA or other tunings).

Here is one (I have no connection to this seller although I did email the seller about a month ago but never received a reply.):

jakesmainstreetmusic.com/produ...5xV3ETiZA

Ken

That seems to fit the bill! (although personally I'd rather do without the fingerboard extension). I will keep an eye out for these vintage instruments going forward.

Another question: does anyone in the ITM world actually play these (beyond use as a travel/practice instrument)?

Travel tenor banjo, Regular GDAE tuning, Full 23” scale fits neatly into a mandola softbag, Virtually unbreakable because there’s no headstock to weaken the neck, weights 7lb with a bamboo tone ring. I always try to check it in. Once the airline refused me check in so it just carried it in and put it in the overhead. No big deal.

What is your objection to a mandolin banjo? They can be strung with 4 steel strings as you want, have a short scale length, & many come with a 10" +- head. Prices on these orphan instruments are very affordable.

30yrs ago, I routinely flew with a standard Tenor (Paramount Style A). Now I'm not sure what size might fit the carry-on limits. A headless MB strung with 4 might fill the bill.

I'd see if I could find a viable string set (5ths tuning) for a banjo uke.

What is a headless MB ?

I assume he means ‘mini banjo’.

I restrung a Slingerland 13" scale soprano banjo uke with the Aquila 30U string set for mandolin-range GDAE fifths tuning a year or two ago (they also offer a set for concert uke for CGDA tuning). They worked quite well on it, though I will say the E was pretty tight on it, not quite to the point of breaking but close. I don't know how steel would work out given the thinner necks some of these have. I'd imagine something more modern like from Gold Tone would be built a bit sturdier, or at least with a thicker neck. 

quote:

---

Originally posted by tdennis

What is your objection to a mandolin banjo? They can be strung with 4 steel strings as you want, have a short scale length, & many come with a 10" +- head. Prices on these orphan instruments are very affordable.

---

It's an option, just not a particularly elegant one (bulky headstock, and I really don't care for the ubiquitous fretboard extension). Vintage mandolin banjos also seem like a bit of a gamble in terms of neck/rim warping. It would make more practical sense to just get a newish entry-level mandolin (except that I really do prefer the sound of banjo). 

Noah -- I have read the same, that the E string is unpleasant. If nylon/nylgut, I'd probably tune DAEB (a 4th lower).