Not likely the engine mounts, or vibes exist in all rpm ranges. When mounts issue, Engine bounces with handbrake applied and clutch slightly disengaged - you can check with bonnet opened
Check following:
Idle mixture settings - adjust till minimum vibrations / Leaner mixture can cause vibes
Carb idle jet functioning - check
All Vacuum pipes for correct connections and health - No vacuum leaks should be there (this issue is in almost many vehicles handled by desi mechanics over the span of years)
Check spark plugs health and plug cables health - they may be causing misfires translating into vibes