The S370 rotates opposite normal, or counter-clockwise. Except for the Kubota B6000, and the old Cubs (which have their own setup entirely), the S370 is rare because it isn't compatible with most implements without some extra work. I've read of people who have reversed mower blades and used the cutter like that; some of the belt driven finish mowers won't work, because the belt tensioners can't function properly.
Augers, obviously, cannot work either. Tillers can sometimes be swapped side for side on tines and made into a functional machine, or, if the construction allows it, the drive axle inverted and everything left alone. Hydraulic pumps can be had in rotations either way, so hydraulically powered implements are doable, but often are sized for much bigger machines.
Non-powered implements will work fine as long as things are properly sized. A small disk, box blade, scraper, plow, etc will work fine behind your machine, and they can do a great job preparing gardens, maintaining driveways or horse arenas, and so forth. Depending on what type of implement and usage you're doing, the size will be in the 4 foot range, as morris9640 mentioned. What you're wanting to do with the machine will really affect what is optimal for you.
A scraper blade used to maintain a driveway or a rake can be bigger, perhaps 5 feet if you're moving things side to side a lot. A bottom plow or disk will work better if it is smaller but heavier/goes deeper. I have a heavy 4' disk harrow that puts a real load on my compact but very dense Yanmar YM186D, a comparable machine to yours that is a half-step larger but almost twice as heavy. It works very, very well, and doesn't need any apologies made for it, though the cut is fairly narrow.
A wider disk won't work well with these lighter machines, since they can't cut as deep and be pulled, or pulled fast enough to flip the soil properly. On my Satoh 1440 (the three cylinder, Japanese market version of your Beaver) that same disk is too heavy, but is doable if carefully managed. The compact tractor implements aren't normally as heavy as this one, which appears to be custom built.
A 42 inch to 4 foot box blade (I have tried both on my ST1440) works well. The 42 inch pulls a little better when heavily loaded or for ripping, the 4 footer covers the tracks more easily, and will smooth loose fill faster.
For gardening, these machines were originally designed to power tillers on commercial farms, and they perform as intended. They are superb tilling machines, having well matched, slow ground speeds available and a variety of PTO speeds. My 1440 came with what is probably a 42 or 44 inch tiller. It works so good that I have just left it mounted, and it is my go-to tilling tractor for gardening. It makes an absolute joke out of a walk behind tiller, even my high quality Honda unit. It actually works a little too well sometimes, leaving frothy tilth that is soft enough to easily bury my hand beyond the wrist.
I prefer to have my implements a little bit smaller than larger, but that's not anything written in stone. I'd just prefer to be able to pull the same implement faster or deeper or more heavily loaded. For my purposes it works better. If you're just maintaining already established landscapes, you can go up a bit in size to speed things up.
Good luck with your new tractor, and congratulations. The Beavers are fine little machines, and I really like mine. Post some pictures!
Finally got it out, what a mess to clean.
