I saw your other thread so I'll answer both here.
Olive eggers aren't a breed. They're a cross breed with one parent being a blue egg layer and the other a dark brown egg layer.
I haven't seen any and not sure what kind of dark egg laying bantams are around. I've heard there are bantam welsummers.
I have hatchery sillies and mine don't lay anything close to a pink egg. Mine lay a slightly off white eggs. They lay about every other day when they're laying. Mine are kinda seasonal. They lay very poorly half the year and the other half lay fairly well but go broody 2 or 3 times a year.
I had some bantam Ameraucana. I won't debate the Ameraucana vs Easter egged debate. They were hatchery stock. They were really neat little hens. Friendly but yet crazy acting at times. All laid very pretty blue eggs and laid almost daily during peak season. They also went broody 1 or 2 times a year.would recommend them for your situation for sure.
Now if you can find bantam welsummers you could get them for a darker brown egger. They might even lay speckled brown eggs. My LF welsummers sometimes do.
Get some bantam Ameraucana and if you can find bantam welsummer you can cross for bantam olive eggers. Or find someone already doing that or that would for you if you don't want to breed or can't have roosters.
You can also cross the Ameracauna with any brown egg laying bantam for green eggs.
Only breed I've ever had that laid what is call a pink egg was a bantam buff Orpington. You can ask around to see if anyone else has or has had them and see what their experience has been with their egg color. If they end up more brown then pink they could still be used to make green eggers.
Hope that helped some.