Now that Dan Schatz has given us one of Les's, I'll give my immediate response:

Here’s to the Les we all remember,
And Reg, who now is but an ember.

His doggy puns will come no more
And Mrs Akroyd waves a paw.

His burial won’t happen yet,
His shroud’s made from his camouflage net.

The wake is in the bar, and there’s -
A dachshund trying to 'mount' the stairs

So raise a glass while you are able.
They’re over there on that ‘table’.

A gin and tonic would be nice,
A polar bear provides the ice.

There'll be no more, There is no Les
And so we say, Good night, God Bless!