FR66S vs Ikeda IT-407 vs FR66FX

The 3 FR66S/IT407/FR66FX are all far too heavy for the Van den Hul.
The premium van den hul cartridges all track 1.35-1.5g and require a low to medium mass tonearm up to 14g effective mass.
If you want to use one of these arms you will need to find another cartridge.

FR64S is best bang for the buck. FR66 is better, but expensive to buy.
66FX I have never heard, but is lighter mass and costs less to buy than 66S. 407 has mixed reviews - most folk believe the FR64S/66 are the best built, and sounding. There have been some reports of quality issues with the Ikeda range ( not built by Ikeda, founder of FR ). The FR’s have the lateral weight balance on the side to balance the whole arm/cartridge, which was omitted on the Ikeda series arms.
One advantage with the longer arms is that you will have lower tracking error with the fixed headshell cartridges such as the EMT/SPU where you cannot alter the tracking angle.
I have had 2 FR64S with no problems.

is tracking force equivalent to compliance. Low tracking force means high compliance and vice versa.

No they are not equivalent, but generally low compliance cartridges tend to track better at higher tracking forces and vice versa.

Some folk like Halcro are using heavy arms with MM's with medium compliance and get away with it, but the top van den hul's high compliance as well as their short cantilever's like on the colibri are a recipe for disaster with heavy arms as noted on van den hul's website ( see Q&A section )..

So it comes back to whether you want to run the van den hul on your 301 as to whether you choose one of these arms.

fwiw amongst many tablesin my collection, I have a 301 with FR64S giving excellent results with suitable cartridges. I have heard the EMTvdh/FR64S combo giving great results, particularly on large scale classical music. SPU's and Koetsu's will of course work well with the 66s/407/66fx.

You might be able to ask van den hul to tweak your cartridge to suit the heavier arms but I suspect he would advise against it. I certainly would never run a VDH on my FR64S. Van den huls own reference for listening  is the SME V  @ 12g effective mass and he tests the cartridges in his workshop on the Technics EPA100.