@Charles *********
there are, but they get expensive, and there are more scams than ligitimate sites. Before I moved here I used Thaifriendly dating site. About half are actually honest lonely women looking to get married, but the other half are prostitutes. You just have to use some street smarts, and filter those that contact you down to a manageable number to meet once you get here. Make a good profile, with pictures, and just stay on the site. Don't try contacting women first. Let them contact you, and they will, lots of them. Over a six month period before I moved here, I narrowed down a list of 62, down to just five that I actually met after I got here. The first one I chose didn't work out after 4 years so I didn't marry her, but the second one I met from that site did work out, and we've been happily married now for 6 years. It is a free site, with a limit on the time between free messaging. With the paid option you get unlimited messaging, but, for the free option after just a few messages with someone you move to Facebook messaging, or talking on the Line app, as most everyone in Thailand used the Line app.
Understand that for a marriage visa extension for the first year you will need bt400,000 in a Thai bank account in your name only for at least two months. Then you can set up your pensions to be transferred directly into your Thai bank account, and Bangkok Bank works the best, because after 12 months of monthly deposits from overseas sources of at least bt40,000 a month you qualify for that financial requirement instead of the bt400,000 method. Something to keep in mind if you intend for a marriage to last long term, is stay away from the ones that work in bars. Lots of women that work in ligitimate jobs don't go to bars to meet people. They use dating sites, with Thaifriendly the most popular. Good luck. You can message me with questions if you want. I am disabled and am knowledgeable about Bangkok, and visa requirements. If you can drive a motorbike it makes it so much nicer living in Bangkok, and being disabled.