Yes, it is still valid for 1 cents worth of postage. Note that the year indicates the date of the Omnibus, not of the stamp. Scott # 1897 was issued in 1981.
1c 1 cent
This is Scott #1897. This stamp is not from 1880s, that is when the omnibus that is pictured is from. It was issued 100 years later in the 1980's and has a minimal value and can be purchased for 15 cents. A dealer isn't going to want to purchase just one.
It costs 25 cents or $4.75 depending on what stamp it is. Hope this was helpful
Stamp
The stamp has to be accepted where you mail the letter. If you are mailing in Canada, you need a Canadian stamp. If you are in the US mailing to Canada, you can use a US stamp.
1 cent.
1 stamp (whatever the current price of a stamp is)
A Postage Stamp.
The orientation of the stamp is not a factor in mailing. It doesn't matter.
There are a number of 1 cent stamps with Washington on them. Consult an online catalog for information to figure out which one you have. That will provide you an estimate on the value.
No, you use the postage of the country where you are mailing the item.
It is 32 cents.