There are many threads on tailoring in Bangkok throughout this forum. I live and work in Bangkok and I've used Milan Suit quite a bit for both shirts and pants. Recently I just had my first shirt done by Narin, and I like it a lot better than the shirts I had done at Milan. Part of the problem was me--I had some bad ideas, and he complied. Part of the problem is the fabric: I teach Art, it gets messy, I thought I'd save money by buying the cheapest cotton shirting. Not happy in the long run. Shirts at Milan start at about 1,200 baht. Shirts at Narin start at 2,000 baht. Narin always uses mother of pearl buttons. Milan use thick plastic buttons.
As for shoes, well, right now I'm looking into options. Ready-made is not so easy for me here at size 47. I"ve found Loake here but they stop at 44. I'm probably going to go custom as I won't be traveling out of Asia any time soon. Haven't decided who I'll try for the shoes. One guy posted a thread on here about shoes with lifts, and linked to a shoemaker in Bangkok that specializes in those. In spite of that poster being lambasted for wanting lifts, I may give the shoemaker a try. He quoted 6,000 a pair ballpark, and can do shoes without lifts. What interests me about this shoemaker is that he's Scottish, and thus hopefully would have a better familiarity with traditional English styles. I may also look into a shop called Maneesilp at Siam square, and haven't ruled out Liu's Bootery and Siam Bootery although I do find both shop's alligator cowboy boot window displays really unappealing.