"Plumbing Problems? Call RENT-A-JOHN!" joke

Plumbing Problems? Call RENT-A-JOHN! We have all types of portable johns to help solve your waste disposal crisis.
Eight Comfortable Models to Select From:
Dear John
(the double seater)
Head of the Class
(our campus special)
Johnny-Come-Lately
(six months of free suppositories)
Johnny-on-the-Spot
(fast operation model)
Farmer's Haven
(need we say more?)
Johnny-Jump-Up
(with floral motif)
Johnny-Be-Good
(a toilet-training favorite with parents)
Can-Can
(comes with bidet; imported from France)
Contact RENT-A-JOHN, a subsidiary of JOHNS-R-US
Number 2, Relief Prospect
Flushing, NY