There are several Indian States that are quite possible to complete.
For example, Bhor:


These two are undoubtedly legitimate issues, and catalogue a grand total of £12 in Gibbons, though you can find them for rather less. There is a debatable third stamp of Bhor:

which can be found with these delightful vanity cancellations. Some authorities question the legitimacy of this stamp though: it may have appeared after the Bhor State Post Office closed.
If you don't want to be bothered with shades, Jhalawar State is another easy one:

and even cheaper, at £7.25.
And if you prefer the simple/simplified life, you can do Wadhwan State in a single stamp:

for £13.
If you want to make life harder for yourself, you can try finding these stamps on cover

or intact sheets

and I could go on ...