Reddit mentions of TRENDnet Powerline 1300 AV2 Adapter with Built-in Outlet Adapter Kit, Includes 2 x TPL-423E Adapters, IEEE 1905.1 & IEEE 1901, Gigabit Port, Range Up to 300m (984 ft.), TPL-423E2K, White

Something like this may be up your alley.

https://www.amazon.com/gp/product/B07B5BTKS3

There are also versions that have a wifi access point built in. Potentially much better than a mesh network IMO.

I'm a little late to your question but here's my two cents:

1. Nothing will be as good as running a cable. CAT5E or CAT6 won't really matter much for most users. CAT6 will get you past the 1Gbps speed at certain distances, but CAT5e supports 1Gbps at 100 m (about 300 ft). CAT6 is also more expansive and more difficult to work with (the strands are thicker which means they won't bend as well and they are harder to crimp connectors). The cable and connectors to do this will cost less than the Moca or powerline adaptors, but obviously you have to install the cable and that can sometimes be prohibitive. You could hire an electrician and he could possibly do it for less than $100, so don't rule that out either. Modular jacks can be terminated in a wall jack without the need to crimp, like Leviton (https://www.amazon.com/Leviton-5G108-RW5-QuickPort-Cat-5e-White/dp/B00029IYUM/ref=sr_1_4?s=electronics&ie=UTF8&qid=1539285173&sr=1-4&keywords=leviton+wall+jack). All you need is one cable and you can connect multiple devices in your office and even put in a wireless access point so your phone has a good connection.
   
   
2. Barring the cabling option, I think powerline is the next best option. A pair like this (https://www.amazon.com/gp/product/B07B5BTKS3/ref=oh_aui_detailpage_o02_s00?ie=UTF8&th=1) will only cost you $70 and will give you speeds of a few hundred Mbps in most cases. It's cheap, easy, and reliable. I have personally experienced that these work pretty well, although not as good as real CAT5 cable.
   
   
3. If for some reason you must go with Moca, a pair like this (https://www.amazon.com/Actiontec-Bonded-Ethernet-Adapter-ECB6200S02/dp/B013J7O3X0/ref=sr_1_1?s=electronics&ie=UTF8&qid=1539284526&sr=1-1&keywords=moca%2Badapter&th=1) will cost you around $170. I have personally experienced that these are mediocre performance wise, but it depends on the coax wiring in your house. If you only have a 2 or 3 way splitter, and it's RG6, and not that long, they might perform OK. But if you have a 5-way splitter or a long distance over RG59, these will not perform well. In addition, you should install a MOCA filter (https://www.amazon.com/TiVo-Authorized-Point-Entry-Filter/dp/B01EKCL1U6/ref=sr_1_2?s=electronics&ie=UTF8&qid=1539284803&sr=1-2&keywords=moca+filter&dpID=31qi88Oe0PL&preST=_SY300_QL70_&dpSrc=srch) on your main cable line to prevent your network traffic from getting to the outside pole, where somebody could conceivably sniff it. All of these Moca adaptors will reduce your cable signal a bit and could lead to some boxes not getting their required signal, resulting in channel dropout or digital noise in the picture. I can't think of a scenario where Moca would work better than powerline adaptors.