I can't remember if my replacement compressor came with oil, but I'm pretty sure the little booklet that came with it said whether or not you needed to add oil. You should also be able to call the manufacturer and ask.

https://youtu.be/uqu8Q_p91oY?feature=shared

There's a quick video on where to add PAG oil. Also, not every system requires the same amount, or even the same type of PAG oil some being 4 oz, 8 oz, some being PAG 46, 100, Etc. So do be sure to check the requirements for your vehicle, often they're printed under the hood around where you'd find your belt routing diagram but also could be on the compressor or elsewhere. If all else fails perform a quick search online and you'll find it.

The above video shows them adding the PAG oil AFTER installation and while it's already running which I wouldn't advise you to do with a brand new compressor, this next video I'm linking is a pretty quick and simple guide to everything you'll need to do before actually charging it.

https://youtu.be/xjem4nmZhQY?feature=shared

Oh, and FWIW, an orifice tube should be fairly inexpensive at your local parts house. The best AC guy I know always gets one in advance and replaces it anytime he even recharges idk if that's maybe too excessive but I will say that almost every orifice tube we've pulled out together has been in need of replacement so there's that.

Ah, and read where you've searched online, is there not a parts store near? I know that O'Reilly's, AutoZone etc. Have where you can look up parts online, maybe check there? I often just go the parts store route for the warranty so if there's an issue I don't have to ship things back and can just swap and re-order at the store. Aside from that, online wise Rockauto is decent if you haven't tried there already

Oh, and make sure the compressor comes with new shader valves! You'd figure it would be a no brainer that they're included but I've gotten them that were bare bones.

While on that subject, if you don't get the correct O-rings with the compressor you can get a universal kit at most parts stores cheaply, that way you can swap the seals on the dryer and whatnot if you wish.

Once again, any questions just ask and either I or someone more well versed in AC installation/charging will get to you

Kudos for getting your own gauges btw! Keep them in a nice, safe spot so you can continue to use them for years to come

As another mentioned, Texas weather this time of year should be fine haha, don't worry I'm only a state or so away and even most of our "cold" days are fine for AC though some would recommend you do it on a not so cold day, being in Texas it shouldn't be hard to find an 80° day this month, I'm standing in one right now lol

One last thing, buying a cheap little UV light to check for leaks may not hurt if you don't have one already as catching a leak quick will save you in the long term