What type of contouring do you use?
Liquid and then foundation or foundation and then cream or powder? will depend which contouring brush to go for possibly!
these are all great for eye showdow?
213 great for getting colour on the eye lid
217 (id get a couple to be honest) blending brush, also great for a very sheer eyeshadow look
219 pencil brush, great for fine line in the crease or similar near the lash line, or precise application in the corner of the eye or anywhere on the eye lid
231 small shader brush, its flatter so is good for blending left and right rather than out, also good for packing on lose pigments etc,
239 medium shader brush, is similar to above but bigger, if you can only get one think about your eye shape, do you have a lot of lid if so go for this one, if not go for the 231
266 small angle brush great for brows, powder eyeliner or creating a line of eye showdow
263 also a small angle brush similary to the 266 I´d get one for brows and one for lid.
316 techically a lip brush but works fab for powder under the eye etc. similar to 219 but smaller.
224 is also very useful if you do cut crease or shading of the crease tapered blending brush, also good for putting softer colour into the crease and then blending at the same time!
210 and 211 are both eye liner brushes, I prefer to use a 212 which is more flat and square but it is personal choice!