Brand name: "Danko Field Elephant" Trousers and Jacket with reflecting stripe on the back. 280THB in local outdoor stores. The set comes in orange, dark green, blue.

I have a set since 3 years and I cover distances of 200km, even, or when I cannot avoid it, in rain. The trousers and Jacket kept me dry until today, and no flapping at all, highly recommended for the cost-conscious rider.

why need raincoat a boxer for swimming does the trick and your skin is allready waterproof

Just bought one for 12gbp in sportsdirect,in stoke,its for my 12yo stepson,got a bag to fold it up in too.High quality and should last him a good while,unless the <deleted> loses it lol lol

There are a number of motorcycle shops around town that will sell you something sturdy that doesn't blow over your head on a bike, because it is made for bike riding - just over a grand for the jacket and pants, and well worth it. they are also vented, so you don't get as hot as you would in a bin liner. Try 'The Paddock' on Rachadapisek - they have a decent set for 1300 baht.

I would caution against Paddock in Ratchada in Bangkok, If you know your stuff, they have some decent things, but when I was a total newbie there they sold me old stock helmets and gloves, after I have found other shops like Panda Rider and Dirt Shop I rare go back there for anything, Last time I was there the boots selection was quite good though, and parts like visors are always in stock, compared to Panda rider that might need to order one it for you.

Back to topic though, I use the outer layer of Columbia camping jacket to wear over my normal riding jacket and that works pretty well

In Pattaya, the Mityon Shop both the main office opposite Tony's and Kawasaki and new Big Honda Showrooms on Sukhumvit have plenty of jackets, even the branded 'sport' jacket (like a shell suit jacket) with no protection works better in the rain than the emergency plastic one you get from Supermarkets. I bought one in an emergency once to ride back from Trad, by the time I got to Rayong it has completely disintegrated, quite funny actually.