Have you looked to the Olympia SG1 ?

Here is mine but with a replacement space bar from a SG3 model.
.

First off, WJC, there's no reason you would need to spend that much money for a standard typewriter in good, working condition. I typically spend on average $40 (CAD) for a standard. Most will need a bit of cleaning and may not look factory new, but they are workhorses that you can use to type a novel.

You have a good short list. I own examples of each with the exception of the Messa, which I've never seen in my area and don't think it's very common in North America. Realistically, what you end up picking will likely be determined by what is actually available in your area (unless you want to risk having a standard shipped and hope that the seller really knows what they're doing).

Of the models you listed I'll admit that I'm partial to the FP, but that's a purely subjective opinion. I like using all three, but there's something about the design of the FP that speaks to me.

 

Finally, as Pete suggested, an Olympia SG-1 is not a model you should ignore. It's likely my favorite standard and the example currently on my desk has been used to type 100k+ words so far without any issues.

Here is my 1960 Royal FP that I got late last year on Shop Goodwill for $ 62 all-inclusive.

It just needed a deep cleaning, polish out of oxidized paint, service, and new ribbon which I did as a DIY project.  It weighs 29.3 lbs. so can still be moved around relatively with ease.

I did add the ivory-cream colour to the ribbon cover to break up the grey-tones of the machine.  And I reapplied paint to the "Royal" logo along its back panel.

I have two (2) Royal Futura 800 portables...and this FP types like a very big brother.  Quite enjoyable to use for long-spells.
.

I have several of the older Royals ranging from a Model 10, KHM, KMM, HH, etc.  Back in the 1960s I trained on the FP.  I got to use others in class but I always preferred the Royal for one reason or another.  Currently I was able to save a KMM and next to the SG-1, it is my favorite.  The KMM is heavy, more than the HH, and though I haven't analyzed it as to why yet, the key action seems to have a more solid feel with less of a "twangy" feedback through my fingers than the HH and why the HH is in storage.  The Olympia has great action with cushioned key tops that I can see would be less fatiguing going through 8 hour shifts in a typing pool.  All these posts about a FP brought back memories, maybe I have to find one.  A couple of things about the FP I remember are the ribbon spools are more generic  and the platens come out with a flip of a lever.  This made switching platens easy as Ames in the day had various types of platens offered.

Another Standard to keep an eye out for is the Facit T2 Standard.

Mine is from 1971 and has a wider 15" carriage.

It's typing action feels light & nimble and doing work for hours does not tire me as my Olympia SG1 seems to.
.