Suggestions for a sub for pine nuts? Almonds OK?

Oh sh*t; I just realized you're serving the pesto on bread. That might be weird.
Use the nuts.

I've made pesto ca' muddica many times (with breadcrumbs in place of nuts). It's very tasty and adds a very nice texture.
Grate an old piece of bread on the large holes of a box grater (or just use fresh breadcrumbs) and toast them in a little garlic-infused olive oil in a pan. Then drain them on a paper towel while you make the pesto. Serve them on top rather than pounding (or processing) them into the pesto as they will get soggy.

Or just use toasted walnuts.

I still think a nut milder than walnuts and higher fat than almonds would be better both taste-wise and for mouth-feel. Pine nuts are mild and high in fat--characteristics of both macs and cashews. Or if you want to stay in the Mediterranean region, perhaps pistachios would be interesting.
Whatever you try, Mollyh, report back!

Cannot imagine macadamias in pesto. I'd sub walnuts or leave the nuts out altogether. Pesto does not have to have nuts.

I would try a nut with a higher fat content like macadamias or cashews.

I second KimmyV. Almonds tend to impart a fairly strong flavor. I usually sub walnuts for pine nuts

When I can't afford pine nuts I go for walnuts.

Coarsely chopped hazelnuts or slivered almonds work great, and are a lot cheaper!