You can get a replacemnet hoop and screws for probably about $25 bucks at any of the drum supply shops.
I always promote:
http://www.drummaker.com/shop1
The odds are that your floor is a 16" diameter tom, with 8 lugs (almost every kit from the 1970's & 80's had one.
)
Andy has one of these going for $11.30 right now.
Remove and measure the length of one of the tension rods (the screws that tune the drum) that you have, and then look for one that is the same length.
Also, when you order, tell them you need tension rods to fit an oldd Roger's kit...just to make sure that these will work....either that, or you will also have to purchase inserts. for the lugs as well (Most drums are now created using a metric threading system, and the older tension rods are a little bit different than the new ones.
OR
You can go without bottom heads.
Go download the song "
Heaven and Hell" by
Black Sabbath.
That yields a typical singleheaded tom sound, and contrary to popular belief - most kick drums are still recorded without a Front head - because people are used to the sound.
I'm seriously thinking about building a set of single-headed toms to go with my kit, because I've found that the three CD's that I spend the most time listening to are
The Mob Rules,
Heaven and Hell, and
Born Again by
Black Sabbath and one of the things that I love is the way that these records sound...they have a .....a timeless sound to them for me....
For heads, I suggest Pinstipes for the Batter/top heads (no matter what you route you choose) and if you choose to go with bottom heads, I would suggest either a set of clear ambassadors for the resonant/bottom heads, or a set of clear "diplomats" for the resonant/bottom heads.
These are all Remo heads.
I can't really tell you about other companies, because I just use Remo. (To make a long story short - I like to use all the same type drum heads on my kit for a uniform sound. I have a 20" diameter floor tom..and that sized tom was discontinued about 20 years ago, but Remo still makes heads that will fit on them.....so I buy Remo.
Tim