Found this which seems to work:
[font="Times New Roman"]SELECT GETDATE() --your query to run
raiserror('',0,1) with nowait --to flush the buffer
waitfor delay '00:00:10' --pause for 10 seconds
GO 5 --loop 5 times[/font]
With the only issues being-
1) It appends to the results window - would rather it overwrote
2) No end-time, though suspect that could easily be done, or I could use simple arithmetic to run for a fixed period.