Where to find all/most variants of a glyth? As far as I know, for one glyth (ex.: 御) there many variant forms.

Some sources list 䘖䘘禦 as variants, others say that all of the glyths in string 御䘖䘘䢩禦衘馭 are variants of 御. 

Is there a reliable source where I can find all (or most of) the variants for a given glyth. I need only CHARS, that is those you can type with in modern PC.
i would use 教育部異體字字典:

http://dict.variants.moe.edu.tw/variants/rbt/home.do

it's authoritative, and most comprehensive.

eg 御 (u+5fa1), it listed 37 variants :)

http://dict.variants.moe.edu.tw/variants/rbt/word_attribute.rbt?quote_code=QTAxMjk1

have fun :)