PT 40 is a good choice, as is the Futaba 6XAS and OS 46 FX.
I'd get a 10 X 6, an 11 X 5 and a 12 X 4 prop. This will give you a decent range to try.

OS A-3 glow plugs would be fine in that engine.

Here's some info I've posted before in answer to questions about building materials and flight line equipment.

Glues: 30 minute and 5 minute epoxy, with something to mix it on and with, (old plastic lids and wooden coffee stirrers, plus small plumbers' acid brushes). Thin CA. (Not "Superglue".) You can substitute wood glue for the CA, but it adds time to the build.

Tools: XActo knife and extra number 11 blades. (Buy a box of 100, it's cheaper and you'll use them.) Razor saw; Kona or XActo. Kona is better. Steel straight edge, 18". A ruler will work but.... Sanding block and various grits of sandpaper. (80, 120, 200, 400.) Screw drivers, small and medium sizes, both flat and phillips types. Pliers, needle nose and regular. (At least one pair with side cutters for wire.) A good set of Allen or hex wrenches. (IMO, Ball drivers are a bit better if you can find a good set.) A "Dremel" type rotary tool will help a lot if you can shell out the extra dollars.

Covering tools: A sealing iron. A Trim iron will help too if you can swing both. A Heat gun made for covering. (Blow dryers don't really get hot enough.) More of those #11 blades for your XActo knife if you didn't buy the box of 100.

Check the kit (or ARF) contents. Most will have a list of extras you'll need to buy; like wheels, fuel tank (& size), fuel line, etc...

By the way. You should buy the engine and radio equipment when you get the plane. You'll need them all to finish the plane, and in some cases, you’ll need them to get started. Buy an engine on the larger size of the recommended range.

Some type of "flight box". (A plastic tool box of appropriate size and design works well. Some good ones at Lowe’s or Home Depot. A gallon of 10% fuel, a fuel pump, manual or electric and fuel line (3 feet minimum),. A glow igniter with charger. Although not 'necessary', I highly recommend a 12 volt starter for the engine, because most new engines are quite hard to start with a "chicken stick", and it’s one more headache you don’t need when beginning.

If you buy a 'self contained' glow ignitor and starter, and a manual fuel pump, you won't need to buy a 12 volt battery with charger, nor a "power panel" to connect everything. (And you won't have cords dangling around your prop when trying to start the engine.)

Then, get a few props of slightly different diameters and pitch (in the recommended range). The engine directions should give you a range of appropriate sizes for your engine. One or two extra glow plugs should last you through the learning process.

The single most important thing that I would recommend getting is an instructor to help you learn to fly. They are also the single least expensive item you can get (free), and the single best piece of insurance that all your hard work building that plane will not be destroyed.

Good luck and have fun.
Dennis-