Favorite lamp from my mom

This lamp was in my home growing up.(1960-2000) It reminds me of my mother who is deceased 15 yrs now. She loved earthy, unique things; collected driftwood, rocks ect. -She loved simple lines. This casts a beautiful warm glow and creates a peaceful ambiance. The glass was accidentally broken, and I am searching for some way to replace it if possible. The square cork base is 8 inch wide by 4 inch tall, with a 6 inch x 3/4 pressed board base below, and a 6 inch circular fitting cut out on top. The lamp shade is 8 inch square frosted crackle glass. The only marking is a Underwriters laboratories, Inc portable lamp issue B - 3050, with E-21232 as well. Any help in finding a similar replacement glass shade would be greatly appreciated!