Best case scenario is to find a way to do cleans. What is it about your gym that prevents it?
I've had some luck moving my deadlift up with accessory work in a circuit.
Something like three rounds of weighted back extensions, RDL or SLDL, GM and fast pulls from the ground.
I'll find a weight that's manageable for all of the barbell exercises for 5-8 reps. For me, setting the bar in the 185-255 range for three exercises is a nice conditioning workout that also moves my deadlift. Obligatory disclaimer: YMMV and you might die.