The amp itself doesn't look that impressive... I mean it's got a metric ton of distortion, all of which can be substantially diminished, but that's not the topic here.
If you want to do it all in SMD, and as cheap as possible, then one option is NP0/C0G dielectric SMD caps. The C8 cap is part of the feedback path, so ideally, you'd want all the caps connected to this path to introduce little to no additional distortion. I'd avoid any X7 or Y5 dielctric caps. Those are really horrible for this kind of job. Besides the fact that their capacitance will be all over the place, you might finnd that they can mess with your feedback network.
Ideally, the caps like C4, C6, C8 would be something like polypropylene or polystyrene ones, but those only come in THT versions. The nearest SMD version would be metalyzed PPS caps. Something like this perhaps:
http://ro.mouser.com/ProductDetail/Panasonic/ECH-U1H102GX5/?qs=sGAEpiMZZMv1cc3ydrPrF%252bfZ13WJ%2fr1%2f%252bZfA9jFk2cU%3dId higher voltage ratings are needed, you'd have to do a parametric search and see if there's any in stock.
These, I think, are better that the C0G caps and at little additional cost.