Are these your speakers? There appear to be multiple models in the line.
They are 4 ohm speakers but have good sensitivity at 88 dB so they shouldn't be too difficult to drive unless you like it really loud. Of the 2 receivers you mention I do like Marantz but know little about the Integra. The Denon X3500H has been discounted for a bit now and would have a touch more power as well as some other cool features, namely Audyssey XT32 room correction that works nicely for integrating a subwoofer or 2.
Amazon.com: Denon AVR-X3500H 7.2-Channel 4K Ultra HD AV Receiver with HEOS, Black: Electronics
www.amazon.com
It's still plenty current for most of today's needs too. If you can squeeze a little more out of the budget that AVR should keep you in business for quite a while.
Accessories 4 Less also has a pretty big selection of older models and factory refurbished receivers too, like this
Denon X3300W. That's a very nice receiver, but it's a few models older so make sure it would have the features you need. A4L is where a lot of us have gotten some of our gear and had great experiences, tho I've heard a couple of hiccups. Make sure to check out their return policy before purchasing.
Accessories4less: search result for "Receiver"
www.accessories4less.com