Does anyone know where I can find a flash hider like the picture below for a Mini 14?  Thank you in advance!

pretty sure Fulton sells M14 flash suppressors.

ETA yep

Flash Suppressor, FA, NM, M14 / M1A

Flash Suppressor, USGI, M14 / M1A

A real USGI one or an aftermarket one?

I should have clarified, sorry.  I am looking for one to fit on a Mini 14.   I have found them without the bayonet lug, but would like one with the bayonet lug.

Accuracy Systems has an adapter to use a real M14 flash suppressor on the Mini-14. https://www.accuracysystemsinc.com/M14-M1A-Style-Flash-Hiders.php

The one the OP pictured is a John Masen which is really cheap and was discontinued.  I would suggest something else like the Choate.
https://www.riflestock.com/store/product/m-14-look-a-like-flash-hider-stainless-steel/

IMHO, and purely based on aesthetics, the "Short" Choate "Recoil Compensator"  (which is actually an effective A2 style flash suppressor/front sight combo), looks better (in proportion) on the shorter/smaller Mini than the "Long" Choate unit.

Functionally speaking the Long" style of flash suppressor in first post seems to me to be needlessly too long, and its forward mounting points might be inferior in strength to the "Short" Choate combined with a bayonet lug further back on the barrel.  This style of muzzle device was also sold by Federal Ordnance (and maybe others).  Originally available in both blue and stainless, and with/without bayo lug.  Some models had drilled holes immediately forward of the front sight, and were actually muzzle compensators which accentuated muzzle flash instead of reducing it.  IIRC, models with drilled holes were "Approved" by BATF as NOT being a "flash suppressor".  Example HERE  Eagle also made similar flash suppressors, also discontinued.

The "Short" Choate will accept common M-7 bayonets, but the user must install a clamp-on bayonet lug from Cogburn Arsenal  Users of early "Pencil-barrel" Mini-14s may find that mounting a clamp-on bayo lug may prevent mounting a barrel strut.  Given the accuracy improvements demonstrated by a dual-clamp barrel strut with respect to the "Pencil barrel" Mini-14s, I'd opt for the strut and the combo Short Choate unit and omit the bayo lug.  YMMV.

I am not sure which model of bayonets the various types of "Long" flash suppressors were designed to accept, but the much more common M-7 is usually much cheaper than other models.

Thanks for all the replies guys.  I ordered the "long" Choate flash hider.  I couldn't see spending more on just the M14 to Mini 14 adapter to still have to buy the M14 flash hider as well.

When the "long" Choate gets here, I will do some mock ups and see if a bayonet will still be able to fit with the lug mount.

Years ago I bought one like this at a gun show.  Not sure who made it, but it looks like this one

https://innovativeindustriesllc.com/m14-style-flash-hider-mini-14/

Item pictured kinda reminds me of a slip-on device made by Eagle.  I could be wrong.

I have one similar to this only it has the holes and not the slits.  It's for the skinny barrel.  I never used it.  I took it out of the bag and tried it on the barrel and took it back off again.. It's really heavy and messed with the balance of the rifle.  

kwg

Hammer, threads on a normal 1/2-28? That might look interesting on an AR-rpk build