Based on this product's specifications, here are some alternatives and similar models
Koelner D-TU-101 Bolt-Down Post Support 101 mm
Summary description:
The Koelner D-TU-101 is a bolt-down post support designed for stable and secure mounting of wooden posts to concrete surfaces. With a 101 mm diameter, this durable steel support provides reliable structural integrity for fences, pergolas, and garden structures. Its bolt-down design allows for easy installation, ensuring the post remains elevated from the ground to prevent moisture damage and decay.