Plantar Series Orthotic Insoles Fallen Arches, Plantar Fasciitis, with Arch Support

Can these be washed in a washing machine?

Would these be helpful if I have high arches? I'm thinking about replacing the current insoles in a pair of (quite flat) Nike shoes.

Ive purchased a pair of 8.5-10. The arch feels too close to the heel. Is there something available with the arch further forward?

I am between a UK7 and UK8 - What size should I order? The shoes I would like to try them in first are HiTec walking shoes size 8.