I work nights for a large retail chain (Hint: its logo consists of concentric red and white circles.) I've always known the Health & Beauty department sold condoms and lubricants, but last night I discovered something you might appreciate.
Trojan makes an inexpensive vibrating cockring that you don't have to go to an adult bookstore to buy. A condom is included with the ring. The ring is made of a soft clear plastic that feels like Gummi Bear candy and there are two micro-vibrators about the size of a .38 caliber bullet on opposite sides of the ring. They can be turned on and off separately by tiny switches. The vibrators are surrounded by tiny fingers meant for clitoral stimulation, but I've slipped the ring onto my cock just below the head, turned on both vibrators, and had several intense orgasms. The vibrators have a life-span of about 30 minutes total.
So look in the Planning & Protection section (near the pharmacy in most stores) and let me know via comments how this tiny, cheap device worked for you.