Dennis
The schemes look believable, the place for this is here
http://airfield.narod.ru/yak/yak.htmlif you look at the left side bar there are various links, keep goind down, it has Yak-1, 3, 7, 9...
on this page
http://airfield.narod.ru/yak/yak-1/yak-1_color3.htmlthere is white 5 with red nose.
either use translate, but just look for "фото" means photo, as that is what makes this site amazing, as it has profiles and the photos they are taken from.
For example - white 5, which is the scheme I'd pick
Лейтенант П.М. Чувелев возле своего Як-1Б. 427 ИАП. Август 1943 г
"Lieutenant PM Chuvelev near his Yak-1B. 427 IAP. August 1943"
Looks accurate to me, down to the note of light coloured cockpit framing.
I'm sure you could find the other schemes.... but I'm guessing white 5 is the one you'd pick?