You can extend your H-1B status as long as you still have time left on that status. You don't need the visa stamp for the H-1B extension, the visa stamp is needed when you travel and re-enter the US. As long as you have the I-94s to show valid H-1B status you are fine.
I agree with Ms. Recob, but I recommend that you meet with an immigration lawyer to go over your situation in detail. Your consultation with an immigration lawyer will not only help you understand the answer to your question, but will give you guidance on what immigration options are open for your future.
Visa no, status, yes.
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