There's some options, though it becomes really specific to your ability. I made a youtube vid talking about the general issues of self defense with mobility issues last year.
Here's some things to look at more specific to your question:
Can you pivot on your weak leg?
In some cases of leg weakness, people end up "locking" the leg. While this ends up restricting your overall mobility to step with it or spring off of it, you can certainly get some rotational pivot from either the ball (if your stronger) or heel (if your leg is weaker). If this is the case, look at techniques that might do ok pivoting off the left leg (kicks with right leg, elbows from the right, some strikes). You may end up having to develop a specific delivery variation for your body for some other techniques.
Elbow and shoulder checks
Your left arm may not be fast but you can probably get in some solid shoulder or elbows from that side if you can twist from the torso or get a good angle from stepping with your right leg. In my younger years I did judo at a dojo with a severely disabled man whose arm was locked into a position in front of his chest - he'd grab you with his good arm and shoulder twist down for take downs all the time.
A pretty great close range tool and not a bad option if you have to shoulder check someone and be up close anyway. There's some wrestling and close grappling styles that also use the chin to grinding to the side of someone's temple or jaw hinge to cause immense pain.
Grappling and ground work
Although ideally in self defense scenarios, your goal is to get away, the fact is you're more likely to end on the ground than fully able bodied folks, so it's good to have your tools together. Part of this should include falling training, simply because that can hurt you more than the hit that knocked you down.
Grappling may also give you ways to use your left arm or leg as a support to another technique, even if they themselves are not fast or strong.
Consider Self defense tools
If your primary concern is self defense, look into what you can legally carry in your area and what tools you'd feel comfortable using - pepper spray, stun gun, flashlight, etc. Practice being able to access it with your good hand and aiming/using the tools as needed.
If you have a brace for your leg or arm, a crutch or cane, or other mobility tools, consider practicing moving around with them, both for your own mobility and for the sake of what kinds of attacks you might be able to make with them.