Until it's added (if it's added), you can do:
alias wtimer {
var %i = 1, %n = 0
while ($timer(%i)) {
var %timer = $v1
if ($1 iswm %timer) {
inc %n
if ($2 == %n) return %timer
}
inc %i
}
if ($2 == 0) return %n
}
//echo -a $wtimer(bla.*, 0)
//echo -a $wtimer(bla.*, 1)
Not likely to have any real performance issues unless you have hundreds of timers running (which is likely to be a performance issue in itself).