Need y'all's expertise...

Left handed shooter here. I know, I know I'm sorry about it too. I recently purchased the left handed version of the 590a1. I love it. Great shotgun. It has a 20inch barrel.
I've also been considering going through the class 3 NFA process of getting a tax stamp for a SBS.
Do you guys know of any way I could get a 14inch left handed 590a1 barrel for the 590 I already own? Mossberg only produces the 20 inch barrel for the left hand model. Not an 18.5 inch. Not a 14 inch.
I'm pretty sure I'm out of luck on this just wanted to an opinion from some people with experience about potential after market solutions.
Thanks in advance!

Bad news - they don't have a production LH 14" barrel.

Good news - a decent gunsmith can do the work on the 20" barrel once you secure the tax stamp, and install a new bead or ramp front sight installed at the same time.

Thanks for the reply!

There are also two takedown rings (or a takedown ring and bayonet lug?) on the 20 inch barrel. Is it possible to remove those and have a takedown ring put back on at the appropriate spot on the shortened barrel. Sorry if that's a dumb question....

Around how much would gunsmithing like that cost? I'd imagine not cheap.

Oh, a 590? My mistake, thought we were discussing a 500.

If you have this gun - the only lefty 590 listing I could find, with 9-round capacity -

https://www.mossberg.com/product/590a1-9-shot-left-handed-59815/

Then you can't make the barrel any shorter than the magazine tube. It's not going to be possible to shorten your exact shotgun's barrel for that reason, though you could shorten the barrel of another lefthanded Mossberg with a shorter magazine tube, such as this one:

http://www.mossberg.com/product/500-left-handed-tactical-59817/

That being said, you'd have to measure and see how much of that 18.5" barrel is in front of the band attaching the barrel to magazine tube. It may only be 3" or so, in which case you wouldn't be shortening the barrel to exactly 14". As you can see, a LH SBS is possible, but it'll take some work. The good news it that the work on the 500 shown would cost only about $100, depending on the gunsmith and the replacement front sight you choose.

Thanks again for this info.

I couldn't replace the magazine tube with a shorter one? Or are they permanently attached?

Also, the take down ring that attaches to the mag tube can't be moved to a new location by a gunsmith?

I know this sounds ridiculously complicated but I'm just curious to know if it's possible.

I've shortened the magazine tube several times for customers.  Just cut and thread.  Not rocket surgery.  To do a 14", just shorten the barrel and tube.  You might need to move the forward hanger back but that can be done too.  The pump arm assemble will need to be shortened but you might be able to use a factory shorter one, I don't know if it will work with the left handed parts.

Damn, I didn't even consider the forearm assembly. It would definitely need to be replaced with a shorter one.

Somehow I think a a shorter one from the factory wouldn't fit the left hand version of the 590 receiver because it just has to be that much more complicated. Anyone know?

Why did I have to be left handed?