I've just started using itilestitch [www.sidefx.com] to stitch tiles from husk. And so far I've been providing the tiles literally one by one, like:

Is there an expression like ## or %02d or something, to just say:
or a top node?
Or does everyone use scripts to do this?

For anyone on Windows here's how I did in a powershell terminal:
itilestitch output.exr @(Get-Item *tile* | Select-Object -ExpandProperty Name)