which email service can setup the third party sender?
 

I know fastmail and gmail can setup the third party sender in their system.
My requirement is, since I am using pobox.com for forwarding, sometime I need to reply this message from a real pobox.com address. Since pobox does provide smtp server, so I want to use this smtp server to reply from pobox.com address from within the third webmail system (b/c pobox basic account doesn't provide webmail).

gmail can setup that, but google is totally blocked in my s*** country.
fastmail can do that too, but I didn't subscribe to FM yet.

Any other providers for suggestion? thanks.:)

You can check Mailo out. This is what they state:

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Collecting external e-mail addresses allows you to gather the messages received by all your addresses into your Mailo mailbox.

You can collect messages received by your other addresses for which you have a POP3 or IMAP4 access. For each address whose messages you want to collect, you have to indicate the account login and its password, as well as the mail server to use.

In order to notice the collected messages more easily, you can assign a specific color to each address. Messages collected from this address will be displayed in this color.

To start collecting messages, click on the Start collecting button in your inbox. You can choose to collect either all the addresses you have defined or only one of them.

You can also send e-mails using one of your collected addresses as the sender.
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